Environmental campaigners have long complained about the growth in tourist numbers polluting the once pristine expanses of the world's last great wilderness, Antarctica.

But for a group of hapless adventurers bobbing around in lifeboats, buffetted by a freezing Antarctic wind as their cruise ship lurched lower in the water, it was the busy tourist traffic through the Southern Ocean that ultimately saved them.

Last night, the group were recovering aboard a Norwegian tourist vessel which also happened to be cruising through the area, reflecting on an ordeal which demonstrated that more than 90 years after the Titanic, icebergs still sink ships.

The drama began just before 1am. As the cruise ship Explorer was picking its way through the Antarctic sea ice, it hit what experts believe was a "growler" - a huge iceberg shorn from the Antarctic ice shelf. Despite being built to withstand such conditions the impact caused a hole in the hull and Explorer began taking on water. An emergency operation swung into action and as temperatures dipped below -5C (23F) the 100 passengers and 54 crew abandoned ship and took to the sea in small open top lifeboats.

For the next four hours - as they watched Explorer sink - they waited for someone to come to their aid.

Eventually, the Norwegian cruiser NordNorge appeared. Captain Arnvid Hansen said that although the passengers in the lifeboats were in good spirits when he arrived, they were cold and hungry.

"It was no problem to get them on board. They were picked up from the lifeboats ... and this operation took around one hour," he said.

Speaking yesterday afternoon he added: "They are in our premier lounge now having warm food and drying their clothes on board. Some are cold but none has hypothermia. We are giving them as many clothes as we can."

Hansen said he was planning to head for King George Island where he hoped all the passengers would be able to land.

Among those rescued were 24 people from the UK. They had been taking part in a 19-day tour, starting from the port of Ushuaia on the southern tip of Argentina and including the Falkland Islands and South Georgia.

John Shears, from the British Antarctic Survey (BAS), said he had been a passenger on Explorer and said it was well equipped to deal with the challenging conditions in the Antarctic. "I was surprised to hear what had happened. It is ice-strengthened and designed to operate down there and it runs a good safety operation," he said.

According to climate scientists the area where Explorer ran into trouble is warming faster than any other part of the globe. This led to speculation yesterday that there had been a subsequent increase in the number of icebergs breaking away from the ice shelf making the waters increasingly dangerous for ships. But BAS scientists said there was no evidence to back up the theory. "Our information is that there was nothing out of the ordinary in the area at the time," added a spokeswoman.

Shears said there had been a huge growth in the number of tourists visiting Antarctica in the last 10 years. But he added that its popularity as a tourist destination had made the area safer. "In this instance it was other tourist boats that came to help and that was what allowed this rescue to pass off relatively smoothly," he said.

Yesterday it emerged that UK Maritime and Coastguard Agency (MCA) inspectors had found five faults with Explorer when it docked at Greenock, Inverclyde in May. These had included missing search and rescue plans and lifeboat maintenance problems. Watertight doors were described as "not as required", and the fire safety measures also attracted criticism.

But a MCA spokesman said the problems "were not huge" adding: "[They] were all rectified before the vessel sailed. It would not have been allowed to depart if everything had not been sorted out."

A spokesman for Explorer said it had had a subsequent safety check in the US in October and been given a clean bill of health.

Explorer, built in 1969, is regarded as one of the best-known specialist cruise ships in the world.

It pioneered the tourist market for Antarctic tours and last night a spokesman for the vessel's tour company, Gap Adventures, said it had an excellent safety record.

"The M/S Explorer hit a lump of ice off King George Island this morning and the impact left the vessel with a crack in the hull the size of a fist," he added.

"All passengers and crew have been evacuated, they are all accounted for and are safe and well."

Wish you were here?

There were 6,000 visitors to Antarctica in 1992 and 30,000 in 2006/07, of which 9,693 were Americans, 4,518 British, 4,082 German, 2,756 Australian

At least 58 cruise ships from 12 countries ply the southerly tourism route with almost 300 visits a year through the November-March season

The Explorer conducted 12 trips in the 2006/07 season, ferrying almost 1,200 passengers to the Antarctic